A knee airbag includes a cushion portion, which includes overlying panels interconnected along a perimeter connection to define an inflatable volume of the knee airbag. The panels are interconnected within the perimeter connection along one or more interior connections that define inflatable chambers within the inflatable volume. The knee airbag also includes a tether connected to an exterior surface of the cushion portion at spaced locations. The tether has a length that is shorter than the distance between the locations on the cushion portion to which the tether is connected. The tether is configured to become tensioned in response to inflation of the cushion portion and causing a bend to form in the cushion portion.